Current stent graft devices with multiple openings or fenestrations require manual placement of wires into the various openings. With fenestrated stent grafts, both the main body stent graft and the bridging stents are typically delivered from a groin access. There are both advantages and disadvantages to such a configuration. For example, advantages may include only having to make two groin accesses instead of two groin accesses and an arm access such as is required for branch systems with antegrade flow characteristics. However, flow in fenestrated configurations may be turbulent and long term patency rates are typically low. Also, the case planning and procedure are often complex. Finally, such a device may require a long lead time because the device must be custom manufactured to match the specific anatomy of the patient.
To address the challenges of using fenestrated stent grafts, there are certain situations in which a cephalad access approach may be advantageous. For instance, this approach may allow the main body stent graft to be designed with antegrade flow to aid in long term patency. Cephalad access and antegrade flow also may allow the branch to be moved antegrade to the target vessel, which gives flexibility in graft placement. This addresses the shortcomings of fenestrated stent grafts where they require complex case planning, long customization lead times, and complex implant procedures.
Known antegrade branches have limitations. With side branches, an operator is required to select with a catheter and guide wire the opening of each branch along an inside wall of the main body stent graft. When advancing through a multi-lumen stent graft, the operator may be required to advance the guide wire and a directional catheter through a set of sequential bifurcations. If the operator is in the wrong branch of the stent graft, the directional catheter may be pulled back, turned and pointed toward the other branch, and re-advanced to the desired branch. In a stent graft in which the antegrade branch openings are at a common location at a single level in a plane it may be challenging to select the targeted branch. In such a configuration, operators may shoot nephrotoxic contrast dye into the openings of the stent graft to provide visibility of the various openings, which may increase radiation time of the patient and operator, and many times may not provide enough clarity to answer any clinical questions.